Improvement in compressible buttons for telephones



UNITED STATES PATENT OFFICE,

ASAHEL K. EATON, OF BROOKLYN, NEW YORK.

IMPROVEMENT lN COMPRESSIBLE BUTTONS FOR TELEPHONES.

Specification forming part of Letters Patent No. 217,930, dated July 29, 1879; application filed November 18, 1878.

York, have invented a new and useful 1m provement in the Construction of Telephones Worked by a Battery-Current, of which the following is a specification.

My invention relates to the preparation of a compressible elastic button. to be used as a means of difierentiating the battery-current. Hitherto the result has been produced by means of a button of carbon, but it has proved unsuited to my requirements. I have found it necessary to produce something more elastic and less friable- This I efl'ect in the following manner: Any metal that is a sufficiently good conductor of electricitysuch as tin, copper, platinum, &c.is reduced to the condition of a time powder or fine laminae, and made into a stiff paste by means of a liquid composed of gelatine and glycerine. This liquid cementing substance is prepared as follows: One ounce of gelatine is dissolved in from four to six ounces of water, and to this solution about one-eighth of an ounce of glyo- The powdered or laminated erine is added.

metal being moistened with this cementing fluid, it is allowed to cool gradually by the application of a moderate temperature, and when nearly free from moisture is compressed in molds to the required form.

The form may be either spherical, disk form, or otherwise.

Owing to the fact that this cement never becomes hard, but always remains flexible and elastic, the resulting button always remains compressible, and is free from the fault of friability.

As a means of transmitting vibrations through the battery-telephone it has proved most satisfactory, giving very loud results, and proving quite indestructible.

WVhat 1 claim is-'-' An elastic compressible button of any required form, composed of any finely-divided metal or other good electrical conductor, firmly united by means of gelatine and glycerine, substantially as described.

A. K. EATON.

Witnesses:

OHAs. E. WEsT, lVIARION M. EATON. 

